Kernel service interruption via negative JFS shift exponent
Published May 21, 2024 · Updated Aug 5, 2026
Shift-out-of-bounds in the JFS allocator in Linux 2.6.12 through 6.6.2 allows local users to trigger undefined behavior via a crafted filesystem. dbMount accepts a negative db_l2nbperpage value, which later becomes the shift exponent in BLKTODMAP within fs/jfs/jfs_dmap.c. Reachability requires JFS allocation code to consume the invalid on-disk value; published evidence establishes a UBSAN failure and kernel availability impact, but no repeatable privilege-escalation primitive.
Summary
What happened
Shift-out-of-bounds in the JFS allocator in Linux 2.6.12 through 6.6.2 allows local users to trigger undefined behavior via a crafted filesystem. dbMount accepts a negative db_l2nbperpage value, which later becomes the shift exponent in BLKTODMAP within fs/jfs/jfs_dmap.c. Reachability requires JFS allocation code to consume the invalid on-disk value; published evidence establishes a UBSAN failure and kernel availability impact, but no repeatable privilege-escalation primitive.
The record
- CVE
- CVE-2023-52810
- Published
- May 21, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 21, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0cb567e727339a192f9fd0db00781d73a91d15a6
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1a7c53fdea1d189087544d9a606d249e93c4934b
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <491085258185ffc4fb91555b0dba895fe7656a45
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <524b4f203afcf87accfe387e846f33f916f0c907
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <525b861a008143048535011f3816d407940f4bfa
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5f148b16972e5f4592629b244d5109b15135f53f
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8f2964df6bfce9d92d81ca552010b8677af8d9dc
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a81a56b4cbe3142cc99f6b98e8f9b3a631c768e1
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <cc61fcf7d1c99f148fe8ddfb5c6ed0bb75861f01
- Affected versionversion=2.6.12
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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